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FractionsArithmeticElementary schoolabout 0:48

Calculate 4/6 - 6/7: animated lesson

A narrated, step-by-step fractions video lesson with captions. Final answer: -4/21.

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Video with a synthetic English voice and captions. Pick another language for subtitles in that language, or open the interactive version.

Video narrated by a synthetic voice (Piper TTS, en_US-ljspeech-high voice (LJ Speech dataset, public domain)); the steps come from our maths engine and the answer was checked independently. Download MP4 (0.3 MB) · Captions (WebVTT)

Steps on screen

1. The problem
Worked example
4/6 - 6/7
2. Step by step
1. $\frac{2}{3} - \frac{6}{7} = \frac{14}{21} - \frac{18}{21}$
  Rewrite both fractions with the least common denominator
2. $\frac{14 - 18}{21} = -\frac{4}{21}$
  Subtract the numerators and keep the denominator
3. $-\frac{4}{21}$
  Final answer in lowest terms
3. The answer
$-\frac{4}{21}$
4/6 - 6/7 = -4/21
4. Check
- Decimal check: -4/21 ≈ -0.1904761905

Transcript

The problem. Here is the problem: 4 over 6 minus 6 over 7. Exact arithmetic with fractions (results kept in lowest terms).

Step by step. Rewrite both fractions with the least common denominator. The LCD of 3 and 7 is 21. Subtract the numerators and keep the denominator. Final answer in lowest terms.

The answer. So the answer is negative 4 over 21. Fractions are combined over a common denominator for addition and subtraction, multiplied straight across, and divided by multiplying by the reciprocal. The result is reduced by the greatest common factor.

Check. Decimal check: negative 4 over 21 approximately negative 0.1904761905.

About fractions

Add, subtract, multiply and divide fractions, finding common denominators and simplifying the result.

Calculate 4/6 - 6/7: Fractions Step-by-Step Lesson